JSFiddle - React, Tailwind, and code Playground

HTML

<div id="text">Hi</div>

JavaScript

function Person(){}
Person.prototype.favorite_books = [];

$('#text').text('alright');

var george = new Person();
george.favorite_books = ["Curious George"];

var kate = new Person();
kate.favorite_books = ["The Da Vinci Code", "Harry Potter"];

var people = [kate, george];
var people_copy = [];
$.each(people,function(i,obj) {
    people_copy.push($.extend(true,{},obj)); 
});
people_copy[0].favorite_books[0] = "Ender's Game";

$('#text').text("working");
$('#text').text(people[0].favorite_books[0]);